"They were in the preparation process of getting ready to shut down aircraft," said Lynne Tolmachoff, a spokeswoman for the California Department of Forestry and Fire Protection, or CAL FIRE. "They actually located the drone and were able to mitigate the problem."

The drone incident happened during the Sand Fire in late July about 35 miles northeast of Sacramento that destroyed 19 homes and caused the evacuation of 1,200 people.

The other two drone incidents were at the Two Bulls Fire near Bend, Ore., in early June and the 391-square mile Carlton Complex fire in late July near Twisp, Wash., that destroyed 300 homes.

Drones and private manned aircraft are prohibited from flying over and near wildfires, and violations can lead to civil penalties and criminal prosecution by the Federal Aviation Administration.

The lone exception to the no-fly zone is for aircraft involved in fighting the fires.

As with the near-shutdown of aerial efforts during the Sand Fire, it's easy to see to see why.

"On that same incident, one of our air attack flights had a bird strike," Tolmachoff said. "I mean that bird wasn't flying that high, so theoretically the (drone) could have been that high, too."

Fires and aerial efforts to fight them set up a worst-case scenario for having small unmanned aircraft over the scene, said Mike Ferris, a public information officer with the U.S. Forest Service at the National Interagency Fire Center in Boise: reduced visibility because of smoke and low-flying helicopters and tankers.

"They're not flying at 2,000 or 4,000 feet; they're flying above the canopy, and they're coming in to the closest water source to try and load their buckets and their tanks," Ferris said about helicopters. "We won't see these things, they're so small. And by the time you see these things it's too late.

"Same thing with the air tankers. Generally they're coming in low because they want to make their drop 150, 200 feet above the fire if it's feasible, if the terrain's flat. They'll come in low, so the potential for an accident exists."

None of the three drone operators were cited. The incidents in Oregon and Washington were near the fires but outside of the FAA Temporary Flight Restrictions zones. In the California case, the pilot "was talked to by local law enforcement," Tolmachoff said.

Both Ferris and Tolmachoff had advice for drone owners.

"Our intent here is to help with education and awareness that if you have a fire somewhere outside your community or near your community, the last thing we really need is for you to go out and get your hobby airplane out and try and fly it around the fire," Ferris said.

Tolmachoff added: "They are neat, and they're becoming very popular. They're great, and it's fun to watch what people do with them.

"Yet there certain situations in which they should absolutely not use them, and this is one of them."